A-Z of fertility

A

Andrology

The study of fertility in men

Anti-mullerian hormone (AMH)

A woman’s level of anti-mullerian hormone is measured early in the process of fertility treatment or egg donation. The result helps fertility specialists to predict her ovaries’ potential response to drugs that stimulate them to produce more eggs than usual. It can also help to predict which patients may expect low or high egg numbers, and even identify patients at a higher risk of Ovarian Hyperstimulation Syndrome (OHSS) (link).

Antral follicle count

The number of antral follicles present in the ovaries, when counted on day 2-5 of your menstrual cycle. Antral follicles are the small follicles which develop in response to the drugs given during IVF treatment.

Asthenozoospermia

Slow-moving sperm (the male reproductive cell).

Azoospermia

Absence of sperm from the seminal fluid.

B

Balanced Inversion

A chromosome abnormality. A piece of chromosome breaks off, turns over, and reattaches itself back to the same chromosome.

Balanced Translocation

A chromosome abnormality. A piece of chromosome breaks off, and reattaches itself to a different chromosome.

Buserelin

A drug used in in vitro fertilisation (IVF) treatment. It acts on the pituitary gland to down-regulate the body’s own hormone production, and encourage favourable reaction to the other hormone drugs in IVF treatment. It also helps the ovaries to produce better quality eggs in greater quantities.

Blastocyst

‘Blastocyst culture’ is the term commonly used to describe the culture of embryos until they are five days old. A blastocyst has a large number of cells and consists of two distinct cell types. Around 40% of embryos will reach the blastocyst stage and those that do have a higher chance of implanting once transferred. Blastocyst culture is usually recommended for patients with a good number of fertilised eggs (3-4), where it will be difficult to choose the best quality embryos at an earlier stage of development, so it’s better to allow the best embryos to select themselves. This will be discussed with all patients on the day of egg collection and again on the day of fertilisation. Learn more about this advanced technique here (Link to Advanced techniques page.)

C

Cervix

The neck of the womb, which has a canal leading to the uterus cavity.

Cleaved embryo

A fertilised egg which has undergone cell division.

Corpus luteum

During ovulation, the follicle carrying the egg ruptures to release the egg and the resulting structure is known as the corpus luteum. This is responsible for the production of progesterone (link), a vital hormone in pregnancy.

Culture medium

The fluid in which eggs and embryos are grown in the laboratory.

Cytoplasm

The jelly-like substance that surrounds the nucleus of a cell.

D

Donor treatment

A treatment cycle where eggs, sperm or embryos are donated.

E

Ectopic pregnancy

A pregnancy that develops outside a woman’s womb, typically in the fallopian tubes.

Embryo

When the woman’s egg is fertilised by the man’s sperm an embryo is formed. The embryo develops into the fetus.

Endocrinology

The study of hormones.

Endometriosis

A medical disorder. The type of cells that line the wall of the womb are also present outside the womb, either in the ovaries or elsewhere in the pelvis.

Endometrium

The lining of the womb.

Epididymis

A highly convoluted tube that connects the testis (link) to the vas deferens (link). The sperm are moved along the tube and are stored in the lower part until ejaculation.

F

Fibroid

A benign muscle growth in the wall of the womb.

Follicle

Fluid sac that surrounds each egg produced by the ovaries. These are counted and measured via an ultrasound scan during the stimulation phase of your IVF treatment cycle.

Follicle-stimulating hormone(FSH)

Follicle-stimulating hormone. A hormone produced by the pituitary gland that stimulates the growth of egg follicles.

G

Gonadotrophin exogenous oestrogen and progesterone. (GEEP)

This is the combination of drugs used to simulate a menstrual cycle prior to the replacement of frozen embryos. Oestrogen (link) and progesterone (link) are also produced naturally in the body.

H

Human chorionic gonadotrophin (HCG)

Human chorionic gonadotrophin is a hormone produced in pregnancy that helps to maintain high progesterone (link) output, thus helping the uterus accept the embryo. During IVF treatment, HCG is injected to mature the egg follicles and help prepare the uterus for embryo replacement. In an early pregnancy test it is levels of HCG that are detected in the blood in a positive test.

Human menopausal gonadotrophin (HMG)

This is the general name for the drug used in IVF treatment to stimulate the growth of egg follicles. There are many different trade names (eg Puregon, Menopur, Gonal-F). They contain FSH (link) alone, or FSH and LH (link).

Hysteroscopy

An operation in which a thin telescope is inserted through the neck of the womb into the cavity of the womb. Small polyps and fibroids can be removed by hysteroscopic surgery.

I

Intracytoplasmic sperm injection. (ICSI)

A procedure to overcome low sperm count, motility, or antisperm antibodies by injecting a single sperm into the egg. (link to treatment page)

Implantation

The embedding of the embryo in the lining of the womb.

In vitro

A Latin phrase, meaning “in glass”, referring to the ‘test tube’ in which fertility treatments originally took place.

L

Laparoscopy

An investigation of the woman’s reproductive system using a thin telescope inserted through the navel while the patient is under general anaesthesia. Although no wider than a fountain pen, the telescope magnifies the surgeon’s view of the fallopian tubes, the ovaries and the uterus. This procedure is vital in diagnosing certain causes of infertility, such as blocked tubes, endometriosis (link) or adhesions (link).

Lutenising hormone (LH)

Luteinising hormone is a hormone produced by the pituitary gland, that controls ovulation. The ‘LH surge’ indicates that ovulation will occur in about 36 hours. The LH surge is stimulated by the increase in oestrogen in the blood created by the growing egg follicle.

Luteal phase support

These are the supportive drugs that you start taking after egg collection, and continue with until after embryo transfer.

M

Menopur

Motility

How well sperm move. Low sperm motility can be the reason why some couples need help to conceive.

N

Nuchal test

A prenatal scan that can identify chromosomal abnormalities associated with conditions like Down Syndrome. The Harmony Prenatal test is a highly accurate nuchal test with very low false positive/negative rates.

O

Oligoasthenoteratozoospermia

Low sperm count, with a high percentage of slow-moving and abnormal sperm.

Oligozoospermia

Low sperm count.

Oocytes

Eggs.

Orgalutran

A drug used to suppress ovulation.

Ovarian hyper-stimulation syndrome (OHSS)

A potentially serious complication when fertility drugs are used and too many follicles develop in the ovaries. The symptoms include lower abdominal pain, swelling of the abdomen, nausea, vomiting and sometimes shortness of breath. Treatment involves bed rest with increased fluid intake and in rare cases hospitalisation and intravenous fluids.

Ovarian Hyperstimulation Syndrome (OHSS)

A potentially serious complication when fertility drugs are used and too many follicles develop in the ovaries. The symptoms include lower abdominal pain, swelling of the abdomen, nausea, vomiting and sometimes shortness of breath. Treatment involves bed rest with increased fluid intake and in rare cases hospitalisation and intravenous fluids

Ovarian reserve

Women are born with their lifetime supply of eggs in their ovaries – the ovarian reserve is a woman’s ‘store’ of eggs. Women’s eggs are gradually used up as they menstruate and age until very few eggs are left. The menopause then begins and periods will stop. The reserve of eggs falls particularly fast in women over the age of 40. Fertility also reduces with age falling to low levels ten years before the menopause.

Ovary (ovaries)

Ovaries are the organs that produce eggs. Women have two ovaries.

Ovulation

The release of an egg from the ovary mid-way through the menstrual cycle. This is the optimal time for fertilisation to occur.

P

Polycystic Ovarian Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a common condition that affects how a woman’s ovaries work.

PCOS affects millions of women in the UK.

The three main features of the condition are:

cysts that develop in your ovaries (polycystic ovaries)
your ovaries do not regularly release eggs (ovulate)
having high levels of “male hormones” called androgens in your body
You will usually be diagnosed with PCOS if you have at least two of these features.

Polyp

A benign growth of the lining of the womb (endometrium (link)). If large, could potentially affect the chances of implantation of the embryo.

Progesterone

A hormone secreted in the body that helps to prepare the uterus for the implantation of the embryo. Progesterone levels can be measured in the blood stream and show a marked increase after ovulation has occurred.

S

Sperm

The male reproductive cell, produced in the testes.

Super-ovulation

The release of several eggs from the ovary as a result of fertility treatment.

T

Teratozoospermia

High levels of abnormal sperm.

U

Ultrasound

Modern diagnostic equipment that works by aiming ultrasonic sound waves and displaying visual interpretation of the echoes on a screen. Vaginal ultrasound is an internal use of this equipment to provide a clear view of the ovaries, follicles, fallopian tubes and womb. Ultrasound is also used in pregnancy to provide a diagnostic picture of the fetus.

Uterus

The womb – the part of a woman’s reproductive system in which the embryo grows.

V

Vas deferens

The tube connecting the testis where sperm are made and stored (via the epididymis(link)) to the urethra.